Cytomegalovirus infection in pregnancy.

CMV is the most common cause of intrauterine infection in this country, affecting approximately 1% of newborns. As such, CMV infection is a leading cause of deafness and an important contributor to learning disabilities. The virus is transmitted through close contact with infected secretions as well as transplacentally, through sexual contact, and through blood transfusion and organ transplantation. CMV has a high prevalence in the population; antibody to the virus can be detected in 50% to 85% of individuals. Like herpes simplex, the virus can be reactivated and cause recurrent infection. Congenital disease occurs in about 30% to 40% of women with primary infection. Ten percent of infants with congenital infection will have clinical disease at birth. Of these, as many as 30% die. Ninety percent of survivors have sequelae such has deafness, mental retardation, chorioretinitis, and motor deficits. The other 90% of infants with congenital infection are asymptomatic at birth, but 5% to 17% develop long-term sequelae. Congenital disease also occurs with recurrent maternal infection in about 0.2% to 1% of immune women. Congenital infection due to recurrent disease is far less severe, and less than 10% of affected infants have long-term sequelae (Fig 3). The diagnosis of congenital infection can be established using a combination of ultrasound, amniocentesis, and cordocentesis. Viral culture of neonatal urine can confirm the diagnosis after birth. Routine screening of the pregnant population is not currently recommended because present laboratory methods limit the ability to differentiate primary from recurrent infection. Preventive efforts at this time must focus on good hygiene, limited intimate contact with infected children, and responsible sexual practices.